Where do I enter auto repair expenses as a real estate professional?

[MinhT1]

You enter auto repair expenses as Vehicle expenses when entering income and expenses for your business (Schedule C).

Please note that you can only deduct auto repair expenses when you opt for the actual expense method, and not when using using the standard mileage method. 

And you can only deduct the business portion of your vehicle expenses.

Please read this TurboTax article on Business Use of Vehicles  for more information.